Publication:

A study of central corneal thickness and psychological wellbeing: a menstrual cycle correlation

Background Hormonal changes during the menstrual cycle can influence ocular physiology. Prior studies report mid-cycle increases in central corneal thickness (CCT) and modest intraocular pressure (IOP) changes. Mean CCT may rise ~5–6% at ovulation, whereas IOP differences are generally minor. These cyclical changes may affect clinical ocular measurements. This study aims to investigate variations in central corneal thickness (CCT) across different phases of the menstrual cycle and examine the potential associations between these variations and psychological factors such as stress, anxiety and depression.

Methods Sixty healthy women (18–30 years) with regular 28–32-day cycles were recruited. Examinations were conducted in the early menstrual phase, midcycle and late luteal phase. Central corneal thickness was measured by pachymetry; IOP by Goldmann applanation tonometry; and visual acuity by a standardized logMAR chart. Psychological status was assessed at each phase using the depression, anxiety and stress scale (DASS-21). Correlation analyses were performed to explore associations between CCT and psychological scores. All measurements were taken in the morning to minimize diurnal variation.

Results CCT was lowest in the early menstrual phase (530.6±8.9 µm), peaked at mid-cycle (561.3±10.1 µm) and decreased in the luteal phase (535.4±9.5 µm), with statistically significant differences (p<0.001). IOP and visual acuity remained stable throughout the cycle. DASS-21 scores were highest during the luteal phase (depression: 8.9±3.1, anxiety: 9.4±3.3, stress: 10.2±3.5) and CCT correlated negatively with anxiety (r=–0.51, p=0.002) and stress (r=–0.46, p=0.004).

Conclusions Menstrual cycle-related hormonal changes cause temporary mid-cycle increases in CCT, while IOP and vision remain stable. Additionally, CCT variations are inversely related to psychological distress, highlighting the importance of considering both menstrual phase and emotional status in clinical ocular assessments.